Methods of forming microelectronic devices
A method of forming a microelectronic device comprises forming a microelectronic device structure assembly comprising memory cells, digit lines coupled to the memory cells, word lines coupled to the memory cells, and isolation material overlying the memory cells, the digit lines, and the word lines. An additional microelectronic device structure assembly comprising control logic devices and additional isolation material overlying the control logic devices is formed. The additional isolation material of the additional microelectronic device structure assembly is bonded to the isolation material of the microelectronic device structure assembly to attach the additional microelectronic device structure assembly to the microelectronic device structure assembly. The memory cells are electrically connected to at least some of the control logic devices after bonding the additional isolation material to the isolation material. Microelectronic devices, electronic systems, and additional methods are also described.
1 . A method of forming a microelectronic device, comprising:
forming a microelectronic device structure assembly comprising memory cells, digit lines coupled to the memory cells, word lines coupled to the memory cells, and isolation material overlying the memory cells, the digit lines, and the word lines, wherein forming the microelectronic device structure assembly comprises:
forming a first microelectronic device structure comprising a first base semiconductor structure, the digit lines, the word lines, and access devices of the memory cells coupled to the digit lines and the word lines;
forming contact structures coupled to the digit lines within digit line exit regions neighboring the access devices in a first horizontal direction;
forming additional contact structures coupled to the word lines within word line exit regions neighboring the access devices in a second horizontal direction;
forming further contact structures within socket regions;
after forming the further contact structures, forming storage node devices of the memory cells over and in electrical communication with the access devices of the memory cells; and
forming routing structures over the storage node devices of the memory cells, at least some of the routing structures coupled to the further contact structures and in electrical communication with the storage node devices;
forming an additional microelectronic device structure assembly comprising control logic devices and additional isolation material overlying the control logic devices;
bonding the additional isolation material of the additional microelectronic device structure assembly to the isolation material of the microelectronic device structure assembly to attach the additional microelectronic device structure assembly to the microelectronic device structure assembly; and
electrically connecting the memory cells to at least some of the control logic devices after bonding the additional isolation material to the isolation material.
2 . The method of claim 1 , further comprising forming capacitors within the socket regions, at least some of the capacitors coupled to one or more of the further contact structures.
3 . The method of claim 1 , further comprising selecting the isolation material of the microelectronic device structure assembly and the additional isolation material of the additional microelectronic device structure assembly to each comprise a dielectric oxide material.
4 . The method of claim 1 , further comprising:
bonding a second microelectronic device structure over the routing structures to form a first assembly comprising the first microelectronic device structure, the contact structures, the additional contact structures, the memory cells, the routing structures, and the second microelectronic device structure;
vertically inverting the first assembly;
removing a section of the first base semiconductor structure after vertically inverting the first assembly to expose portions of the contact structures, and the additional contact structures;
forming sacrificial structures on the exposed portions of the contact structures and the additional contact structures; and
forming the isolation material over the memory cells and the sacrificial structures.
5 . The method of claim 4 , wherein forming an additional microelectronic device structure assembly comprises:
forming a third microelectronic device structure comprising a second base semiconductor structure and the control logic devices at least partially overlying the second base semiconductor structure;
bonding a fourth microelectronic device structure over the control logic devices to form a second assembly comprising the third microelectronic device structure and the fourth microelectronic device structure;
vertically inverting the second assembly;
removing a section of the second base semiconductor structure after vertically inverting the second assembly; and
forming the additional isolation material over the control logic devices.
6 . The method of claim 5 , further comprising:
removing a portion of the fourth microelectronic device structure of the additional microelectronic device structure after attaching the additional microelectronic device structure to the microelectronic device structure;
forming contact openings vertically extending through a remaining portion of the additional microelectronic device structure and the isolation material of the microelectronic device structure to expose the sacrificial structures;
selectively removing the sacrificial structures, after forming the contact openings, to form void spaces in communication with the contact openings; and
filling the contact openings and the void spaces with conductive material to form additional contact structures.
7 . The method of claim 1 , further comprising:
forming routing structures over the control logic devices and in electrical communication with the control logic devices and the memory cells; and
forming pad structures over and in electrical communication with the routing structures.
8 . The method of claim 7 , wherein:
forming routing structures over the control logic devices comprises:
forming tungsten routing structures over the control logic devices and in electrical communication with the control logic devices and the memory cells; and
forming copper routing structures over and in electrical communication with the tungsten routing structures; and
forming pad structures comprises forming aluminum pad structures over and in electrical communication with the copper routing structures.
9 . A method of forming a microelectronic device, comprising:
forming a first semiconductor wafer comprising access devices within array regions, digit lines coupled to the access devices and terminating within digit line exit regions neighboring the array regions, and word lines coupled to the access devices and terminating within word line exit regions neighboring the array regions;
forming digit line contact structures extending through and in contact with the digit lines within the digit line exit regions;
forming word line contact structures extending through and in contact with the word lines within the word line exit regions;
forming capacitors over and in electrical communication with the access devices to form memory cells within the array regions;
forming a second semiconductor wafer comprising control logic devices;
attaching the second semiconductor wafer to the first semiconductor wafer such that at least some of the control logic devices of the second semiconductor wafer are positioned within the array regions of the first semiconductor wafer;
forming additional contact structures over the digit line contact structures and the word line contact structures, some of the additional contact structures in contact with the digit line contact structures, some other of the additional contact structures in contact with the word line contact structures; and
forming routing structures over the control logic devices and the additional contact structures, the routing structures in electrical communication with the control logic devices and the memory cells.
10 . The method of claim 9 , wherein attaching the second semiconductor wafer to the first semiconductor wafer comprises:
vertically inverting the second semiconductor wafer;
physically contacting a first dielectric oxide material of the first semiconductor wafer with a second dielectric oxide material of the first semiconductor wafer after vertically inverting the second semiconductor wafer; and
annealing the first dielectric oxide material and the second dielectric oxide material after physically contacting the first dielectric oxide material with the second dielectric oxide material to form oxide-oxide bonds between the first dielectric oxide material and the second dielectric oxide material.
11 . The method of claim 9 , further comprising:
forming further contact structures within socket regions of the first semiconductor wafer prior to attaching the second semiconductor wafer to the first semiconductor wafer, the socket region horizontally offset from the digit line exit regions and the word line exit regions; and
forming yet some other of the additional contact structures over and in contact with the further contact structures.
12 . The method of claim 11 , further comprising forming additional capacitors within the socket regions of the first semiconductor wafer and in electrical communication with at least some of the further contact structures, at least some of the additional capacitors in electrical communication with at least some of the control logic devices of the second semiconductor wafer after forming the routing structures.
13 . The method of claim 9 , wherein:
forming digit line contact structures comprises forming the digit line contact structures to physically contact the digit lines and a semiconductor material of the first semiconductor wafer underlying the digit lines; and
forming word line contact structures comprises forming the word line contact structures to physically contact word lines and the semiconductor material of the first semiconductor wafer.
14 . The method of claim 13 , further comprising, before attaching the second semiconductor wafer to the first semiconductor wafer:
vertically inverting the first semiconductor wafer after forming the digit line contact structures and the word line contact structures;
removing a portion of the semiconductor material to expose surfaces of the digit line contact structures and the word line contact structures;
forming sacrificial dielectric structures on the exposed surfaces of the digit line contact structures and the word line contact structures; and
forming a dielectric oxide material over the sacrificial dielectric structures and remaining portions of the semiconductor material.
15 . The method of claim 14 , wherein forming additional contact structures over the digit line contact structures and the word line contact structures comprises:
forming contact openings vertically extending through additional dielectric oxide material of the second semiconductor wafer and the dielectric oxide material overlying the sacrificial dielectric structures to expose the sacrificial dielectric structures;
exhuming the sacrificial dielectric structures through the contact openings to form open volumes, the open volumes re-exposing the surfaces of the digit line contact structures and the word line contact structures; and
filling the contact openings and the open volumes with conductive material to form the additional contact structures.
16 . A method of forming a microelectronic device, comprising:
forming an assembly comprising:
an array of volatile memory cells;
digit lines coupled to the array of volatile memory cells and extending in parallel in a first direction;
digit line contact structures extending through and in contact with the digit lines;
word lines coupled to the array of volatile memory cells and extending in parallel in a second direction orthogonal to the first direction;
word line contact structures extending through and in contact with the word lines;
dielectric oxide material overlying the array of volatile memory cells, the digit lines, and the word lines; and
forming an additional assembly comprising control logic circuitry and additional dielectric oxide material overlying the control logic circuitry;
bonding the additional dielectric oxide material of the additional assembly to the dielectric oxide material of the assembly to attach the additional assembly to the assembly;
forming contact structures coupled to the digit lines and the word lines after bonding the additional dielectric oxide material of the additional assembly to the dielectric oxide material of the assembly; and
forming routing structures vertically over and coupled to the contact structures and the control logic circuitry.
17 . The method of claim 16 , wherein:
forming contact structures coupled to the digit lines and the word lines comprises:
forming some of the contact structures over and in contact with the digit line contact structures; and
forming some other of the contact structures over and in contact with the word line contact structures; and
forming routing structures vertically over and coupled to the contact structures and the control logic circuitry comprises:
forming some of the routing structures to horizontally extend from some of the contact structures to sense amplifier devices of the control logic circuitry; and
forming some other of the routing structures to horizontally extend from the some other of the contact structures to sub-word line driver devices of the control logic circuitry.